1. Field
One feature relates to providing content protection for subscriber-based mobile broadcast services. More specifically, trust is established between an accessory device and host device using a global key determined according to the type of host device.
2. Background
Wireless networking systems have become a prevalent means to communicate with others worldwide. Wireless communication devices, such as cellular telephones, personal digital assistants, and the like have become smaller and more powerful in order to meet consumer needs and to improve portability and convenience. Consumers have become dependent upon these devices, demanding reliable service, expanded areas of coverage, additional services (e.g., web browsing capabilities), and continued reduction in size and cost of such devices.
A typical wireless communication network (e.g., employing frequency, time, and/or code division techniques or a combination thereof) includes one or more base stations that provide coverage areas to subscribers as well as mobile (e.g., wireless) devices that can transmit and/or receive data within the coverage areas. A typical base station can simultaneously transmit multiple data streams to multiple devices for broadcast, multicast, and/or unicast services, wherein a data stream is a stream of data that can be of independent reception interest to a user device. A user device within the coverage area of that base station can be interested in receiving one, more than one or all the data streams carried by the composite stream. Likewise, a user device can transmit data to the base station and/or another user device.
Forward link only technology has been developed by an industry group of wireless communication service providers to utilize the latest advances in system design to achieve the highest-quality performance. Forward link only technology is intended for a mobile multimedia environment and is suited for use with mobile user devices. Forward link only technology is designed to achieve high quality reception, both for real-time (streaming) content and other data services. Forward link only technology can provide robust mobile performance and high capacity without compromising power consumption. In addition, the technology reduces the network cost of delivering multimedia content by decreasing the number of base station transmitters that are necessarily deployed. Furthermore, forward link only technology based multimedia multicasting is complimentary to wireless operators' cellular network data and voice services, as cellular network data can be delivered to a same device that receives multimedia content by way of forward link only technology.
One such forward link only technology is MediaFLO™, by Qualcomm Inc., which broadcasts data to portable access terminals such as cell phones and personal digital assistants (PDA). MediaFLO™ is a subscriber-based service and requires the device receiving the service to have an embedded forward link only receiver. However, service may now be extended to devices that do not have an embedded forward link only receiver. To utilize the service, a user may purchase a forward link only receiver, hereafter referred to as an “Accessory Device” that can stream content to a non-forward link only device, hereafter referred to as a “Host Device”.
Content providers as well as MediaFLO™ service operators mandate that such service deployment is robust against the following attacks: (1) extract unencrypted digital content from the accessory device, the host device, or the communication link between the two; (2) stream MediaFLO™ content to host devices that are not in the specified list of ‘approved host types’; (3) stream MediaFLO™ content to more than one host device at a time; and (4) stream MediaFLO™ content to a host device without the consent of the device owner while it is in his/her position.
However, in MediaFLO™ systems, content is encrypted only up to the forward link only protocol stack (e.g., the accessory device). As a result, the transmission of the content from the forward link only protocol stack (e.g., the accessory device) to the host device is not secure. Therefore, a method is needed for establishing trust between the accessory device and host device.